Inductive energy can accumulate in a power circuit (e.g., switch-based power supplies, automotive applications, and the like) that relies on power switches, such as a power MOSFET (Metal Oxide Field Effect Transistor) type, semiconductor-based switch device, to control the flow of electrical current to a resistive-capacitive-inductive load. The switch-off of a power switch may stop the accumulation of inductive energy and allow inductive energy that accumulated prior to the switch-off. If a short occurs at the resistive-capacitive-inductive load, accumulated inductive energy can begin to dissipate which may potentially damage or even destroy the power switch or the other portion of the power circuit.
Power circuit emergency events (e.g., over load events, short circuits, and the like) can lead to the greatest accumulation and subsequent dissipation of inductive energy in a power circuit. To prevent energy dissipation and resulting thermal damage from occurring at a power switch, some power circuits may include a “Zener diode gate clamp” (referred to simply as “a Zener clamp”) across the drain and gate terminals of the power switch. During an emergency event, a power circuit may try to minimize the amount of inductive energy that accumulates as a result of the emergency event by switching-off the power circuit's switches as quickly as possible. When a power switch that is protected by a Zener clamp is switched-off as fast as possible during an emergency event, a rise in the junction temperature of the power switch will occur during the period of time when the Zener clamp transitions to clamping operation. The momentary temperature rise may damage and even destroy a power switch if the temperature exceeds the maximum temperature rating of the power switch.